Construction material



March 8, 1938. 2. A. HOGGATT 2,110,729

CONSTRUCTION MATERIAL Original Filed Jan. 3, 1933 VENTOR 6/: 85/97 #060 477" BY w r W ATTORNEYQ I Patented Mar. 8, i938 PATENT OFFICE cousrauc'rron MATERIAL Gilbert A. Hoggatt, Snyder, N. Y assignor to Certain-Toad Products Corporation, New York, N. Y., a corporation of Maryland Original application January 3, 1933, Serial No.

Divided and this application Novem' ber 10, 1936, Serial No. 110,080

7 Claims.

This invention relates to construction materials, especially construction materials of fibrous composition. The invention has particular reference to wall -boards"with edges preformed to particular shapes in' 'order to provide tight joints between adjacent boards.

The problems arising in the use of construction materials which must be laid as units or elements of greater. or less size include the proper forma- 1 tion of the joints between such elements to insure continuity of a surface to be exposed or to prevent leakage or infiltration of air through the structure, as well as to provide a proper support at the joint for superimposed surfacing materials. 15 Especially in wall boards which are used in abutted relation to form a continuous surface of the wall is it desirable or necessary that the continuity of the finished surface shall not be marred by the joint and also that the joint shall be strong and of such form as to prevent the leakage of air therethrough, particularly when laid upon an outsidewall. Moreover, the joint should be of such form in many cases as properly to support a plaster applied upon the wall board and over the joint. It is frequently necessary in such 25 cases to provide a lock for the plaster which will assist in preventing cracking and breaking away of the plaster at the joint. 7 i

To accomplish such purposes in various types of construction materials and in wall board, it has heretofore been proposed to form the edges the units orelements or of the wall boards th a so-called shiplap or rabbeted 'edg'e. Such units or boards may be laid with therabbet 35 of one unit lapping upon the reverse rabbet of I 'an adjacent unit. Moreover, it has heretofore 1 been proposed soto form such shiplap or rab beted edges that when the units or the boards are so lapped a space of greater or less width is leftbetween the adjacent edges of the units or boards plaster or other covering aterial may enter to form a lock for said coveri g material and makes, 45 possible a greater thickness of the plaster over 55V and cracking or breakage ofthe plaster or coveron that side thereof which is to-be exposed' This arrangement provides a recess into which.

ing material if such material is applied to the base surface. Moreover, the methods of producing the shiplap or rabbeted edge in many cases have been wasteful, particularly when making provision for the space toform a lock for the plaster "or covering material. 1

wall boards which will avoid waste of material and secure a production thereof at low cost.

In order to provide more effectively for the expansion which ,occurs in construction units and which results in buckling of the units or cracking of the surface thereofor cracking and breaking away of materials such as wall plasters applied thereto, the present invention proposes a form of rabbeted joint in which provision is made for expansion of the joint by means of a space between portions of the adjacent edges of adjacent units while other portions of the edges are in substantial abutment. The edges, however, are so formed that the portions in abutment may yield under the force of expansion without undue deformation or distortion of these portions to effect cracking of the face of the covering material or plaster which occurs when the base is not free to expand is also prevented. 4

- The preferred method by'which the product of the invention is produced comprises the severing of the material from which the unit is to be formed in such a way as to remove a minimum of material, as by a fine saw cut, and the subsequent separation of the two portions of the material along a line connecting the cuts. Such a method is the subject of my prior application, Serial No. 649,777, filed January '3, 1

1933, of. which the present application is a division, and provides for the formation of a rabbeted edgeby making two such saw cuts transversely of the surface of the unit on opposite surfacesof said unit, said cuts being spaced 5 from each other ina direction parallel to the the inner ends of the two outs in the body of I the material.

The invention will be more clearly understood from the following description taken in connec-' tion with the drawing in which:

The figure shows inlone embodiment of the invention an assembly of units having rabbeted edges.

In the figure is shown in cross section the application of the invention to a joint between wall boards. The wall board I is formed at its left hand edge in the figure with a rabbeted recess provided by the surfaces 2 and 3. The tongue 4, of which the surface 2 forms the surface to be lapped upon the rabbeted edge of an adjacent board, is formedwith a bevel surface 5 extending from the v-shaped edge 6 reversely upon the tongue 4. The thickness of the tongue 4 is approximately one-half the thickness of the board I, and correspondingly the depth. of the surface 3 is approximately one-half the thickness of said board. These proportions, however, may be varied within the scope of the invention.

At the opposite edge of the board I and in the. reverse hand from the tongue 4 is formed the tongue it having an end surface ii and a longitudinal surface I2.: The height of the surface II is approximately one-half the thickness of the board. Thus the surface is about at the middle of the thickness of the board. From the inner end of the surface II of the tongue III a bevel surface It extends inwardly toward the center of the length of the board but outwardly toward the upper surface "I thereof to form with the surface If an obtuse angle. The angle of the bevel surface It with respect to the upper surface 'I of-the board may be -substantially the same as that of the surface 8 with said upper surface 1. However, if desired, the angles of these two surfaces may be different to suit partlcular conditions.

It will be noted from the figure showing three .such wall boards; one lapped upon the other, that the V-shapededge t substantially abuts against ,the' bevel surface it of the adjacent board. As

the surfaces 2 and ii are substantially-longitudinally of the wiiith of the board, these surfaces -in adjacent units may move with respect to each other as in any shiplap construction. while these surfaces 2 and I! have been shown asv straight lines, they may be, otherwise formed to suit different conditions provided the form of one with respect to the other is such that the overlapping tongue4 of .one board may move upon the overlapped tongue ll of the adjacent board without substantial distortion of the tongues or substantial movement transversely of the surfaces of the boards. As the V edge of the overlapping tongue 4 moves against the bevel surface it of an adjacent board under the force of expansion, a slight yielding or compression or even a slight crushing of such V edge may occur.

As the edge 0 presents oniya small amount .of

material against the surface i3, such yielding oreven such crushing will ,not produce substantial deformation of the joint and plaster or other covering material applied upon the surface I and extending into the recess II between the surfaces 5 and II ofadjacent boardswili not be subject to an extreme force whlchjwili tend to crack the plaster at the joint and to cause it'to chip off or break away.

While heretofore it has been proposed to use boards presenting a recess, such as that show at ii in the figure, in such prior constructions the edges of the boards have been so formed that when the v edge 6 abuts the surface It the shown in the figure, a space is left between the end edge surface H of the tongue ID of one board and the surface 3 of the rabbet of the overlapped board. When expansion of the boards takes place the edge, l l may move toward the surface 3 without bringing pressure thereon which will cause the boards to buckle or which will bring upon the joint forces which will tend to destroy the joint and cause cracking of the plaster applied thereto. It' now should be clear that to provide the space between the'surface II and the surface} it is necessary to form the surface I! of the overlapped tonguev ill on one edge of the board with less length in the direction of the width of the board than the length in said direction of the surface .2. As may be seen in the figure, thedifference in length (if the sur face 2' and of the surface I! in the overlapped arrangement of the boards leaves the necessary space between the surface H and the surface l for expansion-of the boards when the V edge is abutted against the bevel it.

As a particular example of the proportions which are practicable for the embodiment of the invention, those suitable for a wall board may be given. For so-called insulating lath which is used as a base for plaster or stucco, sheets or panels of the standard size of 96 inches length byv 48 inches width may be reduced to smaller panels of approximately 48 inches by 16 inches to form the insulating lath. The width of shiplap boards, shown in the figure by the dimension A, correspondingly would be approximatelyld inches from the V edge 6 to the corner formed by surfaces l2 and I. As an example of the dimensions necessary for the rabbeted edges, the following may be given: For a thickness of board about it" the length of the surface '1 may be about ti" and the length of the surface I! may be about thus leaving a space of approximately V for expansion. In a board of such a thickness .the depth of the surface 3 is approximately 5 and similarly the dimension of the surface II is approximately V4". Thus the surfaces 2 and I! are positioned substantially at the center of the thickness of the board. The

angle of the bevel surfaces 5 and It may be conyeniently degrees or in some cases the angle which these surfaces make with the surface I upon which plaster is tobe applied may be approximately 120 degrees. Various modifications of the dimensions may be made within the scope of the,invention, and in order to insure alignment of they surfaces 1 slight clearances between the surfaces 2 and I: may be provided for. Moreover, in different forms of units different dimensions and clearances and different angles of the bevel surfaces may be used. It willbe apparent that a movementof one board with respect to the other-mayproduce a compression or a crushing'of the V edge 8 upon the surface II of the adjacent board but that ample space a ar a-m9 v I v takes the edgewise bearing of said rabbet against allowed between the surfaces II- and 3 for such expansion without bringing the surfaces lI-and 3 into contact. y

In order to form the V-shaped recesses or' plane of rotation, i. e., whether symmetrical with said plane of rotation of said cutter or other wise, may be used. Thus in one operation a bevel edge board may be produced in the manner described in my prior application, Serial No.

649,777, filed January 3, 1933. By using in accordance with the process .of said prior application a saw or cutter of proper width for the lower cut the width of the space between the surfaces H and 3 are shown in the figure may be 'imade such as to leave room for expansion of the boards. By suitably positioning the saws or the cutters or the grinding wheels, the dimensions desired for the surfaces 2 and I2 as well as for the relation of the other surfaces of the edges of the board may be obtained.

In applying the invention in the production of units or elements of some kinds of materialthe cleavage or breakage of the body structure of the material along the line of cleavage may result in surfaces which are not sufllciently smooth. These surfaces may result from the tearing away of portions over an emery wheel or other device to;

bring the rough surface down substantially to i the center of the width of the board.

This is the more necessary when units. such "as wall boards are to be arranged upon a supporting structure without any superimposed coating such as plaster which will cover the joint, although in some cases itmay be also necessary to smooth the rough surface in order to insure that the exterior surfaces of two adjacent boards shall be aligned. 7

While the invention has been described and I illustrated more particularly in connection with Wall boards, it is applicable to other types of construction units and construction materials, whether of granular or fibrous or other body structure. In particular, however, the invention is useful in the formation of shiplap edges on panelsof wall boards of fibrous materials which have not a great resistance to crushing of the edge thereof when reduced in thickness or brought to a sharp edge. What is claimed is: l. A structural member having rabbeted edges in generally complementary relation to permit lapping one edge of one member upon the other edge of another member and having one rabbet longer than the other, the shape of that portion of .the member forming the longer rabbet being such as to provide an edge of relatively weak structure with respect to the remaining structure of the member, which edge substantially the other member.

2. A structural unithaving two rabbeted edges for overlapping upon the rabbeted edges of similar units, the length of the rabbet of one edge of .the unit being longer than that of the other edge thereof, the portion of the unit adjacent the long length of the rabbet being beveled on its 1 exterior end surface so to form a V edge with said long rabbet that said V edge substantially takes the bearing of edgewise contact between said similar units.

3. A structural unit having two rabbeted edgesfor overlapping upon the rabbeted edges of similar units, the length of the rabbet of one edge of the unit being longer than that of the other edge thereof, the portion of the unit adjacent the long length of the rabbet being beveled on its exterior end surface to form a V edge with said long rabbet,.the portion of the unit adjacent the}? length being beveled to form'an obtuse angle with said rabbet of shorter length, the remaining 1 interior transverse surface of the rabbet of shorter 39,-.

transverse surfaces of the two rabbets being in I such relation to their respective rabbets as" to provide clearance therebetween when said V edge is in contact with said obtuse beveled edge.

4. A wall board having two of its edges rabbeted ingenerally complementary relation to permit one edge of one wall board to be lapped upon the other edge of another board, the length of the tongue of the, rabbet of one edge being greater than the length of the tongue of the'rabbet of the other edge,. said rabbets being so formed that when the edge of the longer tongue is abutted against the interior end surface of the other rabbet the tongue of said other rabbet will not abut the interior end surface of the first. rabbet,

said longer tongue having its abutting edge of substantially less thickness than the thickness of said tongue to provide yielding contact when in said abutting relation.

5. A wall board having two of' its edges rabbeted in generally complementary relation to permit one edge of one wall board to be lapped upon the other edge of another board, the length of the tongue of the rabbet of one edge being greater than the length of the tongue of the rabbet of.

the other edge, said rabbets being so formed that when the edge of the longer tongue is abutted against the interior end surface of the other *rabbet the tongue of said other rabbet will not abut the interior end surface of the first rabbet, said longer tongue having its exterior end surface so formed with respect to the length of the tongue as to present a relatively weak edge for abutment against said interior end surface of the other rabbet.

6. A wall board having shiplap edges, one of C 'the tongues; of said edges being longer than that of the other, said longer tongue being formed with a beveled edge, the interior end surface of the other shiplap edge of said board being formed relative to said beveled edge substantially to take the bearing thereof under edgewise expansion-of said wall board in two boards with longer rabbet being such as to provide an edge ance between the remaining surfaces of the rabbets which would offer resistance to edgewise' movement of said members withrespect to each other.

GILBERT A. HOGGA'I'I. 

